Sewing machine



Dec.l 10, 1929. B, T, LEVEQUE v 1,739,241

SEWING MACHINE Original Filed Feb. 2, 1924 Patented Dec. 10, 1929 UNITED "STATES PATENT OFFICE BERNARD T. LEV'EQ'UE, OF WENHAI, MASSACHUSETTS, ASSIGNOB T0 UNITED SHOE MACHINERY CORPORATION, OF PATERSON, NEW JERSEY, A CORPORATION 0F NEW SEWING MACHINE Original application illed February 2,

This invention relates to sole sewin machines of the through-and-through or cKay type, the stitch forming instrumentalities of which comprise a straight hook needle and the work support of which consists of a horn arranged to extend within the shoe and rovided at its tip with a looping device or w irl for laying the thread in the hook of the needle. In addition, such machines include shoe feeding devices and a presser foot which is movable relatively to the horn to clamp the work and to release it so that it inay be fed.

The principal object of the present invention is to provide a machine of the above type with needle, presser foot and work feeding mechanisms constructed and arranged to cooperate in a novel and improved manner so that the operating parts of the machine may be timed to run evenly and smoothly at higher speed than machines of this type heretofore devised and the stitches of the seam may be drawn in or set more tightly and in a more uniform manner.

To secure this object the present invention provides such a machine with mechanisms for actuating the needle, presser foot and work feeding device, constructed and arranged to. feed the work during a portion of the retracting stroke of the needle and to depress the presser foot after the work has been fed and before the needle reaches the limit of its retracting stroke. ,The actuation of the needle, feeding device and presser foot in this manner greatly facilitates the timing of these parts and'also the other parts of the machine and makes possible acontinuous and smooth action on the thread in forming the stitches with a conse uent improvement in the tightness and uni ormity of the seam and anincrease in the speed at which the machine can be operated. In a chain -stitch machine in which the stitch is set by the needle this manner of operating the needle, feeding device and presser foot is especially advantageous because it results in the work being held irmly against the horn and compressed while the stitch is bein set.

Another o ject of the present invention is to provide a novel and improved mechanism for actuating the presser foot, and for adjustlment ofthe n 1924, Serial No. 690,265. Divided and this application iled October 19, 1985. Serial No. 68,226.

ing its action in accordance with the thickness of the work, which will operate smoothly and accurately at hi h speeds and eliminate any possibility of sppage and lost motion in this mechanism or other parts of the machine controlled or aected by the operation of the presser foot.

The invention will be readily understood by those skilled in the art from the following description taken in connection with the accompanyingdrawings in which Fig. i is a view illustrating in front elevation the needle, work feedin and presser foot mechanisms of a chain stitch McKay sewing machine embodying the invention, and Figs. 2, 3, 4 and 5 are detail views illustrating somewhat diagrammatically the relative movements of the needle, feeding device and presser foot during a stitch forming and work feeding cycle of the machine. v

Referring to the drawings, the work supporting horn of the machine is indicated at 6 and is provided with a needle threadin device consisting of a whirl 8 constructe and arranged to operate as is usual in this type of machine. The straight hook needle of the machine is indicated at 10, the presser foot at 12 and the feed point at 14.

In embodying the present invention in .the machine, mechanism, the details of which will be hereinafter described, is provided for actuating the needle, feed point and presser foot as follows: y Starting with the palrts inthe position illustrated in Fig. 2, in which the needle is at the l' 't of its retracting stroke, the feed point is at the limit of its feeding stroke and the presser-foot is in its vlowest position, clam ing the layers of the work togetherand ho ding them against the upper surface of the horn. The needle is forced downwardly through the Work to its til its point clears the work, as indicated in' Fig. 4. At this int in the u ward move` e the presser oot is raised slightly, and the feed point is moved into by the whirl, and the needle is retracted unengagement with the work. During the continued upward movement of the needle from the osition indicated in Fig. 4 to that indicateg in Fig. 5 the feed point is actuated to feed the work, the presser foot remaining in its raised position so that the pressure of the work against the bottom of the presser foot and against the upper surface of the horn is relieved. When the needle reaches the position indicated in Fig. 5, the feeding movement of the feed point has been completed, and as the needle continues to rise,

the presser foot is forced down a ainst the Work so as to clamp the layers o material together and press them against the horn, the work being thus compressed and firmly held a ainst the horn during the continued retractmg movement of the needle to the limit of its retracting stroke indicated in Fig. 2. The layers of material, for instance the insole and outsole of a shoe, are thus firmly pressed together and held against the horn while the stitch is being set by the needle, and the entire operation of pulling in the slack thread and exerting a stitch-setting strain on the seam is performed smoothly and continuously. The formation of uniformly tight stitches is thus insured and operation of the machine at a high rate of Speed is made feasible.

The mechanisms for actuating the needle, feed point and presser foot are the same as those of the machine disclosed in applicants pending application Serial No. 690,265, filed February 2, 1924, of which the present application is a division, and may be briefly described as follows: llihe needle is clamped on the lower end of a needle bar 16 which is reciprocated from a crank pin 18 on the forward end of the sewing shaft 20 through the following connections, which connections are provided for the purpose of giving a variable throw to the needle bar as work varies in thickness, and also for the purpose of permitting the needle bar to be disconnected from the sewing shaft at the top of its stroke at the end of the sewing operation. A block 22 is secured to the needle bar and is connected by a link 24 to a lever 26 pivoted at 28 to a lever 30, which lever is secured at its right hand end to a pivot shaft mounted in the machine frame. The right hand end of the lever 26, as viewed from the front of the machine, is provided with a curved slot 32 which is engaged by a block 34 pivotally mounted in the upper end of an arm 36 which is adjusted as the work varies in thickness by connections to the presser foot hereinafter described. When the axis of the block 34 is coincident with the axis of the pivot shaft the lever 26 will move with the lever 30 as the lever 30 is oscillated. If the axis of the block 34 is not in alignment with the axis of the pivot shaft the lever 26 will move with relation to the ,lever 30 during the oscillation of the lever 30 and the movement iinarted to the needle bar increased or diminlshed accordingly. A lever 38 is mounted at the side of the lever 30 and at its right hand end is secured to a sleeve surrounding the pivot shaft of the lever 30. A cam slot 4() is formed in the lever 38, which cam slot is engaged by the crank pin 18 so that during the rotation of the cam shaft the lever 38 is continuously oscillated. To cause the lever 30 to oscillate with the lever 38 a latch 42 is mounted upon the left hand end of the lever 30 and is arranged to engage a pin 44 on the lever 38. During the sewing operation the latch is held in engagement with the pin by means of a spring surrounding the pivot of the latch.

rIhe presser foot bar is indicated at 46 and has secured thereto ablock provided with a laterally extending arm in the outer end of which a roll 48 is mounted which engages a curved slot 50 in the arm 36. As a result of this construction as the presser foot rises and falls with variations in thickness in work, the arm 36 is moved to adjust the block 34 along the slot 32 of the lever 26 and thus vary the upward stroke of the needle bar.

The presser foot is forced downwardly by means of a spring and is raised by mechanism which comprises a block 52 secured to the presser foot bar. 0n the block 52 is pivotally mounted a block 54 inthelower face of which a V-shaped groove is formed to cooperate with a correspondingly V-shaped edge 56 of a lifting lever 58. This lever extends beneath the block 54 and is pivotally connected directly above the block to an arm 60 projecting from a rock shaft 62. This rock shaft is provided with another arm 64 which is connected -by a link 66 to a cam actuated lever 68. The lever 68 extends across the cam shaft 20 and is mounted upon a fixed pivot stud 70. A spring, coiled about the pivot stud, acts on the lever to hold its cam roll in contact with the cam 72. During each cycle of operations of the machine the shaft 62 is rocked to lift the lever 58 into engagement with the block 54, and continued upward movement of the lever causes the presser foot to be lifted. In order that the lifting movement imparted to the presser foot may be constant, regardless of variations in the thickness of the work, means are provided for swinging the lever 58 about its pivotal connection with the arm 60 as the work varies in thickness. This means comprises a roll 74 mounted on the block 7 6 at the lower end of the presser foot bar and a lever 78 pivotally mounted on the machine frame, the upper end of the lever 78 being connected to the lever 56 by a link 80, and the lower end of the lever 78 being provided with an inclined projecting ledge 82 arranged to be engaged by the roll 74. Movement of the lever 78 in one direction is produced by the engagement of llO ' the lever in the oppositedirection is produced by a spring coiled around the fixed pivot pin of t e lever. The arrangement of the edge 56 of the lever 58 with relation to the pivotal connection of the lever 58 with the arm 60 is such that an adjustment of the lever 58 in the manner described, as the work varies in thickness, causes the block 54 to be engaged by the lever always at the same point in the upward movement vof the arm 60 so that the upward movement imparted to the presser foot is always the same.

It will be noted that the mechanism for liftin the presser foot comprising the lever 58 an block 54 acts positivel without requiring the use of locking` or c amping devices such as pawls or friction dogs or clutches, and that thus any possibility of lost motion or slippage, which has been a serious defect in'prior presser foot mechanisms designed for this type of machine, is eliminated. It will also be noted that this presser foot lifting mechanism, although acting positively, is ad'usted from the presser foot, as is also the n actuating mechanism, and that both mechanisms are in effect self-locking, the presser foot actuating mechanism being self-locking by reason of the arrangement of the lifting lever 58 and block 54, and the needle actuating mechanism being self-locking by reason of the arrangement of the slot 32 in the lever 26 with relation to the pivots of the lever 26 and the arm 36.

The feed point is secured in a holder 84 which is pivotally mounted upon a fixed pivot pin projecting rearwardly from a feed point carrier or slide 86. A spring tends to swing the holder in a direction to bring it into contact with the end of the feed point carrier 86. The feed point carrier is mounted upon the block 7 6 at the lower end of the presser foot bar by means of pins Vwhich project rearwardly from the block through slots formed in the feed point carrier. These slots have parallel inclined portions and horizontal portions which are 1n line with each other, the horizontal portions extending in the direction of feed and the inclined portions extending obliqnely to the direction of feed.

The feed poiht carrier is moved back and forth in the lin'e of feed by a lever 88, the lower end of which is connected by a link 89 to the feed point carrier. r1`he upper end of the lever 88 is provided with a cam slot 90 which is engaged by a roll 92 mounted on the lever 30 at the pivotof the latch 42. The lever 88 is acted upon by a spring which moves the lever in a direction to hold the left hand side of the cam slot 90 in engagement with the roll 92. During the sewing operation 'the roll 92 travels up and down in the slot 90 against the left hand side of the slot and thus vibrates the lever 88.

The nature and object of the invention having been indicated and a machine embodying the several features of the invention having been described, what is claimed is:

1. A shoe sewing machine having, in combination a straight hook needle, a shoe su porting horn arranged to extend within t e shoe, needle 'threading mechanism located in the horn, a feeding device acting to feed the work during the retracting stroke of the needle, a presser foot held in raised position during the feed and depressed before the needle reaches the limit of lts retracting stroke, and

means for actuating the parts.

2. A chain stitch shoe sewing machine havlng, in combination, a shoe supporting horn arraniglell to extend within the shoe, needle threa gmechanism located in the horn, a straight'hook needle acting during its retracting stroke to exert a stitch-setting strain on the seam, a feeding device acting to feed the Awork during the retracting-stroke of the needle, a presser foot held in raised position durmg the feed and depressed to clamp the work on the horn before the needle reaches the limit of its retracting stroke, and means for actuating the parts.

' 3. A sewing machine having, in combination, stitch forming devices, a presser foot, an abutment thereon, a' presser foot lifting member moved into and out of engagement ywith the abutment, and means controlled by the thickness of the work and acting independently of the engagement of the member with the abutment for positioningthe lifting member to cause it to engage the abutment at the same point in its lifting movement regardless ofthe thickness o f the work.

4. A sewing machine having, in combination, Vstitch forming devices, -a presser foot, an abutment connected therewith, a presser foot lifting member, said abutment and lifting'member being provided one with a V- shaped groove and the other with a correspondingly V-shaped edge to prevent relative movement during the lifting of the presser foot, and means controlled by the thickness of the work and acting independently of the engagement of the'member with the abutment for positioning the lifting member to cause it to engage the abutment at the same point in its lifting movement regardless of the thickness of the work.

5. A sewing machine having, in combination, stitch forming devices, a presser foot, an abutment thereon, a presser foot lifting member moved into and out of engagement with the abutment, and means controlled by the thickness of the work and. acting independently of the en agement of the member with the abutment or imparting a relative p 6. A shoe sewing machine having, in combination, a straight hook needle, a shoe supj porting horn arranged to extend within the shoe, needle threading mechanism located in 5 the horn, a presser foot mechanism comprising positively acting self-locking adjustable connections for raising the presser foot during each stitch forming cycle, and a separate set of connections from said mechanism to lo'thepresser foot for adjusting said mechanism to lift the presser foot a uniform distance regardless of the thickness of the work 7. A chain stitch shoe sewing machine having, in combination, a straight hook needle, ap shoe supporting horn arranged to extend within the shoe, needle threading mechanism j locatedin the horn, needle actuating mechanism, a presser foot, connections between the presser foot and the needle actuating mechanism for adjusting said mechanism to vary -the throw of the needle as the work varies in thickness, a presser foot mechanism comprising positively acting self-locking adjustable connections for raising the presser foot during each stitch forming cycle, and a separate set of connections from the presser foot mechanism to the presser foot for adjusting the resser foot mechanism to lift the presser foot a uniform distance regardless of the thickness of the work.

8. A sewing machine having, in combination, stitch forming devices, a presser foot, an abutment thereon, a presser foot lifting member moved into and out of engagement with the abutment, said abutment and lifting member being provided with surfaces arranged to prevent relative movement during the lifting of the presser foot, and means controlled by the thickness of the work and o acting independently of the engagement of the member with the abutment for positioning the.lifting member to cause it to en age the abutment at the same point in its li ting movement regardless of the thickness of the work.

9.- A sewing machine having, in combination, stitch forming devices, a presser foot, anv abutment thereon, a presser foot lifting member moved into and out of engagement 5o with the abutment, said abutment and lifting member being provided with surfaces arranged to prevent relative movement during the lifting of the presser foot, and means controlled by the thickness of the work and acting independently of the engagement of the member with the abutment for imparting a relative positioning movement to the lifting member and abutment to cause the lifting member to engage the abutment at the same point in its liftlng` movement regardless of the thickness of the work.

In testimony whereof I have signed my name to this specification.

vs BERNARD T. LEVEQUE. 

